/Engine/Source/Runtime/Engine/Classes/Engine/NetConnection.h
: set to net connection currently insideCleanUp(), for HasClientLoadedCurrentWorld() to be able to find it during PlayerController destruction, since we clear its Player before destroying it. (and that's not easily reversed)
static class [UNetConnection](API\Runtime\Engine\Engine\UNetConnection) * GNetConnectionBeingCleanedUp = NULL;